A mem divides one degree of 41-edo into 5 logarithmically equal parts. This is approximately the size of the JND (just noticeable difference). It therefore divides the octave into 41 * 5 = 205 equal parts.
The mem is therefore calculated as the 205th root of 2, or 2(1/205), with a ratio of approximately 1:1.00338692848311. It is an irrational number.
A mem is:
The formula for calculating the mem-value of any ratio r is: mems = log10(r) * [ 205 / log10(2) ] or mems = log2(r) * 205
A mem represents one degree of 205-edo tuning.
The 12-edo semitone is exactly 17 1/12 (= 17.08,3...) mems.
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